Search Documents

By R. F. Pilgrim

"This first chapter of the SPOC Manual 1s intended as a general introduction to all the other chapters in which the mineral process evaluation and optimization methodology is presented. This chapter also provides a brief description of available software for mainframe and m1crocomputers and provides information on its distribution by the Technology Information Division. CANMETRESUMECe premier chapitre du manuel SPOC est un guide général qui présente les autres chapitres ou l'on traite de la méthodologie d'évaluation et d'optimisation des procédés miméralurgiques. Le lecteur y trouvera aussi une description sommaire des programmes de calcul développés pour ordinateurs centraux et pour micro-ordinateurs ainsi que la façon de les obtenir de la Division de l'information technologique du CANMETComputer simulation of mineral processes has slowly emerged as an established branch of activity in A&D centres and in several teaching institutions after decades of slow progress. Substantial efforts to develop application software based on years of research on process modelling are being pursued in many countries ( 1 .2,3,4.5). The late BO's should see a flurry of success stones about significant leaps of productivity achieved in several plants through systematic process evaluation and computer simulation studies.In Canada. the SPOC project (Simulated Processrng of Ore and Coal) was initiated at CAN MET in 1980 with the obJective of developing and transferrrng to the mineral rndustry a computer-based methodology for process evaluation and optimization. The proiect deliverables include:- an engineering manual covering most aspects of off-line computer simulation:- a bank of FORTRAN software accessible through data communication lines for user familiarization and distributed at a nominal cost in source form by CANMETThe yearly progress reports of the project contain detailed information on the project elements since 1980 16). The context of SPOC can be summed up by quoting Gordon Agar""s 1975 statement during a workshop on research needs in the mineral industry: ""What is needed is a joint effort between the academic community and one or more enliglitened industrial concerns. The effort will have to be an iterative one with data collection followed by testing the model modification of the model (s), more testing prediction, modification. data collection and so on (7). A few parallel in1- t1atives had been reported in papers or research contract reports (8, 9) but there was an obvious need for CANMET to bridge the gap between the R&D and the production sectors by undertaking a project that would document past applications and induce a new generation of initiatives through the consol1dat1on and transfer of suitable manuals and software. The effort took shape as the CANMET SPOC pro1ect in which methodology transfer was to play a key role (10)."

Jan 1, 1986

By Hector Monette

"AFTER SPENDING a lifetime in the mining industry it is normal that one should be concerned with the future of his profession, especially if he is directly responsible for the education and formation of future mining engineers. It is not necessary to insist on the importance of mining for Canada and for the entire world to prove the necessity of the Mining Engineer. A statement was made by Zay Jeffries, former vicepresident of General Electric Co., and here I quote: ""Even though minerals without man are of no moment, man would not be man as we know him without minerals ... ""minerals are as essential to the life of social man as food is to man himself"". This certainly expresses magnificently the purpose of the mining profession. These are the reasons why I have accepted to present my views on the future of the Mining Engineer. If I express some concern it is not because I feel that there is any danger for the profession to disappear; men will always respond to a challenge and this can be found in the extraction of minerals as well as in any other field of human endeavour. However, the first big question concerns the competitive position of Canada in the world of mining. To be made available to Canadians and to the rest of the world, all this tremendous potential mineral wealth that our country has been so generously endowed with by nature must be gained from the earth's crust at a competitive cost. Otherwise it will never become ore and will have no value. Let us not forget that although minerals are discovered, mines are not found but are made. So let us be more efficient mine makers. To accomplish this end, it is the duty of the different responsible organizations at all levels - be they governmental, para-governmental, public or private institutions - to do their utmost to assure the profitable development of our mineral wealth. The University has an all-important role to play in preparing all the specialists required by this intricate machine that mining is. All the different disciplines of engineering, health, social and -managerial sciences are needed for the good functioning of the mining industry. Although they are all essential, some will play a more important role as a member of the structure. In this discussion it is the role of the most important member, the mining engineer, who is actually responsible for the extraction of the minerals from the earth's crust that must be established. From this we will then be able to analyse his responsibilities and try to suggest the mining engineering program most suitable to prepare this engineer for his future role."

Jan 1, 1972

By Balmer Neilly

In these days of arrested prosperity, when patience is tried and the future but dimly outlined, Canada's gold mining industry stands out as a beacon light shedding its rays of hope and confidence and demonstrating that there is still one product unaffected by Customs barriers and eagerly sought by all the people of the world. Some other forms of industry have hesitated and side-stepped. Some have cried for help, and in spite of public assistance, generously extended, they are still unable to demonstrate definitely their ability to resume the onward march. But gold mining has never hesitated. As an industry, it has bad an unique experience. When prices are high and conditions are generally referred to as prosperous, this industry is adversely affected. The cost of production goes up; profits are diminished; public sympathy is lacking; and, thrown upon its own resources, the industry tightens up its belt and throws its whole energy into an effort to improve operating conditions, and offset high prices by increased efficiency. When, in due course, depression follows inflation and prices ebb, the gold miner, through necessity, finds himself physically and mentally prepared to meet the situation.

Jan 1, 1932

By Greg Barnes

Agenda ? The Mining Stock Life Cycle ? Current Environment ? Valuation ? Golds ? Valuation ? Base Metals ? Case Study ? Quebrada Blanca Hypogene Commodity Investment Cycle ? Macro-Economic Indicators ? LME Inventories ? watch the trend; rising inventories ? bad for prices, declining inventories good for prices ? OECD Leading Indicators ? PMIs ? Purchasing Manager Indices ? Industrial Production ? more important for metals consumption than GDP ? Housing Starts ? US, Europe ? Auto Sales ? All things China ? metal imports/exports; SHFE inventories; SRB stockpiling ? Seasonality ? it does play a role ? What is Chris Dutton (TDSI Quantitative Analyst) saying?

May 1, 2010

By A. Vervoort

The concepts of geostatistics are commonly difficult to understand for students, even for those with a strong mathematical background. A main problem is certainly the link between the variation of the parameter value in space or time, and the calculated experimental semivariogram as a function of the interdistance, but over the entire area. Another problem is to differentiate between directional and omnidirectional semivariograms and the way they have to be interpreted. Furthermore first time users of geostatistics often do not want to struggle through different books with the whole geostatistical background before using it. Too often this leads to using geostatistics as a black box with all the risks linked to it. That is the main reason that we developed some interactive tools based on the free public domain software R. We aim by developing three different modules to assist individual first time users, but also regular students and teachers to get a feeling of the importance of the various aspects in conducting a good geostatistical study. The modules show directly e.g. the impact of deleting, moving or adding data points, of changing parameters of the semivariogram model and of the geometrical parameters during kriging. The first module allows making the link between the variation of the parameter values in one direction and the calculated experimental semivariogram, and this for different given datasets. The second module covers two dimensional datasets and apart from calculating the semivariogram values, models can be fitted to the calculated data. A distinction can be made between omni-directional and directional semivariograms, including the effect of the tolerance on the angle and lag-distance. The third module focuses on ordinary kriging of point values in two dimensions. The aim of the interactive tools developed is limited to educational purposes only, i.e. to visualize some basic concepts for different pre-selected types of spatial variation. They do not intend to do a geostatistical study on a certain dataset (for this purpose there exists already a broad spectrum of good software packages). The original intention of developing the three modules was aimed at users with no or a limited amount of geostatistical experience. However, these modules seem also very useful to remain critical for experienced users. One should never forget that in a real application one does not have a complete view of the phenomenon studied. The geostatistical interactive modules can be accessed through: www.bwk.kuleuven.be/geostatistics . We compiled a manual to facilitate the use of the modules and to guide the user we formulated several questions to be solved for each module.

Aug 1, 2013

By M. Maldonado

This work details the application of a decentralized control strategy to a pilot flotation column working with a two-phase system (water-air). The process is represented by a multivariable system composed of three inputs and three outputs. The selected control variables are the froth depth, the air hold-up and the bias rate, whereas the corresponding manipulated variables are the set-points of the local flow controllers of tailings, air and wash water. All controlled variables are estimated using electrical conductivity based techniques. In particular, the results of a new method for estimating the bias rate, based on the measurement of the volumetric fraction of wash water under the interface, is presented. This method reduces the coupling problem associated to the bias estimation as a difference between feed and tailing water rates. Moreover, the nominal system transfer matrix can be represented by an upper triangular matrix, in such a way that the closed-loop system stability reduces to the stability of the independent control loops. The experimental results show that the closed-loop system performance, particularly that of the bias rate loop, is strongly dependent on the air flow rate, reaching in some cases the saturation point of the controller.

Jan 1, 2007

In several European countries, including Russia, it has become economically attractive to utilize peat as a fuel for power generation, the production of metallurgical coke, the production of fuel briquettes for the domestic market and low-Btu gas. Although the economic base and availability of energy supplies in Europe is much different than it is in Canada, regional economics here may warrant the development of peat as an alternative source of energy. Canadian peatlands cover several thousands of square miles and have historically been considered as waste land. Now, with the increasing costs of other energy sources, it is apparent that fuel peat should be re-evaluated as a potential energy resource. A nation-wide inventory of peat deposits has been prepared and reserves evaluated for some of these areas where field surveys have been carried out. The paper describes alternative mining methods developed to meet some of the various conditions encountered on virgin peatland . These mining techniques are generally based on current peat technology exercised in other parts of the world and would be applicable in some of the peat regions of Canada. Cost estimates have been prepared for peat production in regions of Canada, and the socio-economic aspects of a large-scale fuel peat operation are discussed. Several potential utilization schemes have been described, with particular emphasis on electric power generation. The paper makes recommendations for steps to be taken in the development of a fuel peat industry in Canada.

Jan 1, 1978

By F. Habashi

Lead is an ancient metal, has been produced to-date from its ores exclusively by pyrometallurgical route. The process suffers from high operating cost and excessive pollution problems. Extensive research has been going on since the beginning of the twentieth century to find a non-polluting process for its production and a solution for its complex refining scheme. It has been assumed correctly that the hydrometallurgical route should be the most promising. Pilot plants have been constructed and operated for a reasonable periods, but no process has proved to be satisfactory. As a result, a number of smelters and refineries have been shut down. The present review analyses the situation and suggests that the best route to treat lead sulfide concentrates is by leaching with fluoroboric acid, HBF4, containing ferric fluoroborate, Fe(BF4)3, and electrolyzing the solution in a diaphragm cell - - a process recently invented by Italian metallurgists. In this process, any silver present in the concentrate remains in the residue together with elemental sulfur and can be recovered by known methods.

Jan 1, 2008

By H. W. Smith, C. L. Lewis

"A process control computer has been installed in the Lake Dufault concentrator to: (a) control the on-stream X-ray analyzer and convert chart readings to elemental percentages, (b) calculate the flow rates required for the most important flotation reagents, using the amount of material entering the process, the analyses and the slurry pH, and (c) set the reagent feeder to these flow rates automatically. Although this project was largely experimental, to gain knowledge and experience in flotation process control, the objectives have been met and fully automatic computer control is now the normal mode of mill operation.This paper describes project planning and defines the system with respect to both control design and functional design. System operation -as seen by the mill operator -is detailed. Implementation of the system is described and the system is discussed in terms of its success, economic justification and future plans."

Jan 1, 1969

By Omkar N. S. Beruar

Extraction of sill pillars has always been problematic because of high risk of seismicity and rockburst. Depending on a number of factors, a sill pillar can undergo different failure modes and cause problems in the mine. Of these, sudden and uncontrolled failure of part(s) of the pillar leading to highenergy seismic events and rockbursts is a main concern because it is not possible to predict the location and time of a rockburst apart from its potential to cause extensive damage to the mine structures. To date, a comprehensive technique for sill pillar design and recovery does not exist. Conventional methods of pillar design, such as the pillar stability graph method, are utilized to design stiff sill pillars. In these design approaches, the post-peak response of the pillar-rock system is not considered. This is in part due to a lack of clear and comprehensive understanding of the post-peak behaviour and failure mechanism of sill pillars. In general, the strength of a rockmass is described using a failure criterion. When stresses reach the strength of the rockmass, the rockmass does not necessarily become unstable and knowledge of the loads alone is not enough to assess the instability conditions accurately. In fact, it is not possible to predict instability of rockmass based on the strength/stress ratio alone because instability depends not only on this ratio but also on the loading condition and loading system characteristics. The loading system can dictate whether the sill pillar will go through a stable or unstable failure process. This paper examines the influence of various parameters such as the pillar width to height ratio, the extraction rate, and placement of backfill on the Loading System Stiffness (LSS) and the Pillar Stiffness (PSS). The ultimate goal is to design yielding sill pillars that would yield in a stable manner and will reduce the risk of pillar rockburst. Plane strain finite element analysis is conducted using the generalized Hoek-Brown failure criterion with elastic-brittle-plastic parameters. Examples are given to demonstrate how to calculate these stiffness values and assess the stability condition of sill pillars. It is found that increasing the rate of extraction increases the likelihood of unstable yielding of the pillar as has been found in other studies. Placement of backfill in a timely fashion in the stopes above and below the sill pillars increases the stiffness of the loading system. This indicates that backfilling of stopes while creating the sill pillar increases the likelihood of stable yielding of the sill pillar.

Aug 1, 2013

By George S. Rice

Foreword Explosion hazards differ widely in the mines of different fields or coal basins. They also differ as between different mines in the same basin or fold, because of variations in gas entering the mines, and because dust conditions and explosion hazards are affected by the mining methods employed and the organization of the work. It is unquestionably true, however, that there are greater differences in explosion hazards in mines of different coal fields or basins than between different mines of the same field or basin. In these respects, the coal fields and individual mines in Alberta are not exceptional. The same conditions obtain in various countries where coal is mined, and are found in single States, as for example in Colorado, where coals are mined ranging in character from sub-bituminous to anthracite, and in attitude from flat horizontal to steeply pitching beds. The U.S. Bureau of Mines, at its experimental mine near Pittsburgh, Pa., has made large-scale tests of the relative explosibility of dusts of coals, ranging in rank from Wyoming sub-bituminous coal containing 19 per cent moisture, to anthracite from Pennsylvania, and including samples from a mine in the Crowsnest Pass district, B.C., and from a Vancouver Island mine. The Bureau has also made similar tests of the dust of coal from a Yorkshire mine which the British Safety-in-Mines Research Board uses as standard.

Jan 1, 1927

By Jonathan Ruiz Lizardo, Met-Chem Canada Inc., Flavio Ccuno, Constante Umipig, Ewald Pengel, José Ruiz

"Cerro de Maimón is located in the Dominican Republic on the island of Hispaniola approximately 75 kilometers northwest of the capital city, Santo Domingo. The processing facility consisted of two separate processing plants for oxide and sulphide ores. The oxide plant processed oxide ore bearing gold and silver ore using cyanide leaching and Merrill Crowe processes, while the sulphide plant produced a copper concentrate using conventional flotation. Cormidom is a commendatory example how mineral processing facilities can co-exist in balance with the environment. In 2014, natural occurring copper oxide contamination with finer grained copper-zinc sulphide mineralisation was expected to dominate the sulphide ore body. In anticipation Cormidom contacted the original plant designer Met-Chem to assist in overcoming this challenge. Test work indicated that increased flotation time and subsequent very fine grinding were required. Met-Chem provided the detailed engineering and Cormidom proceeded with the expansion project internally. Currently Cormidom has processed the sulphide ore successfully by implementing flotation modifications. This paper describes the history of Cormidom, test work on the “new” ore body, modification in process design in the Cu-Zn sulphide flotation circuit, construction and implementation.INTRODUCTIONCorporación Minera Dominicana (CORMIDOM) was a wholly owned subsidiary of GlobeStar Mining Corporation (a Canadian based minerals exploration company) with extensive exploration of base and precious metals in the Dominican Republic. In 2007-2008 CORMIDOM constructed the Cerro de Maimom project. The company was subsequently sold and purchased by Perilya Limited from Australia in 2013. Cerro de Maimón is located in the Dominican Republic on the island of Hispaniola approximately 75 kilometers northwest of the capital city, Santo Domingo. It is near the town of Maimón in Monsenor, Nouel Province (see Figure 1)."

Jan 1, 2016

By G. Wilson

"Satisfactory hydraulic performance of a centrifugal slurry pump is not the only design criterion. If abrasive wear exists the severity of any damage can be reduced and the life of the wearing parts prolonged by selecting the correct pump to suit the conditions of service. This paper is concerned with the design and construction of centrifugal pumps for handling abrasive solids. The wear phenomena due to the slurry being pumped and the materials used to combat abrasive, wear are outlined. The hydraulic design of the impeller and casing and their relationship to wear and the hydraulic radial and axial unbalance are discussed. The prediction of abrasive wear in pumps can not be precise, as many factors are involved - and this is the object of current research."

Jan 1, 1973

By Dayang Datu Khalil, Charle Amoah, Fred Kock

Abosso Goldfields Limited has been optimizing the comminution circuit at the Damang Mine Operation for the treatment of 100% primary ore. The optimization process started at a base rate of 343 tph when treating primary crushed primary ore, and was increased to above 600 tph with partially crushed primary ore. Abosso Goldfields engaged Orway Mineral Consultants (OMC) to assist with the optimization process in 2009 and the two companies have been working together since, to further refine the process. Continuous improvement was achieved through crushing circuit modifications, changes in operating processes and grinding control system utilization. This paper discusses the improvements developed for the increase in milling capacity and improvements in final product size.

Jan 1, 2012

By P. -M. Tardif, S. Outalha, R. Le

"This paper proposes a new direction to implement an underground mine communication system. It presents actual underground communication systems and discusses their technological limits. A new system based on a wireless local area network (WLAN), together with its main systems characteristics, is then proposed. This paper also presents an experimental protocol for radio frequency propagation measurements. Finally, the paper describes the projected implementation of a WLAN in an experimental mine. IntroductionDuring the last decade, a number of Canadian mining companies have invested in modern communications systems in order to automate processes and reduce operational costs. Safety of miners is also a concern, regulated by health and safety regimes.Underground communication systems rely mainly on analog technology (especially the leaky feeder). Digital upgrades have been made to modernize this technology using a coaxial or fibre optic cable to transmit voice, documents, commands, controls, and video. Therefore, all wired equipment can benefit from an increase in efficiency from the digital technology.However, when it comes to mobile equipment, the only medium was, and is, still radio waves. With the advent of the wireless local area network (WLAN) standard, one can use a technology similar to that of the cellular phone to connect transparently different equipment. WLAN enables the transmission at rates higher than 2 M bits of voice, documents, commands, controls, identification, and of course, digital video. This technology was developed with inbuilding use in mind. Now, one can try to adapt it to underground mines."

Jan 1, 2000

By F. Hassani, E. Aflaki, M. Nokken, M. Kermani

"This paper presents and compares the physical properties of Gelfill and cemented hydraulic fill (CHF) obtained by lab experiments. Gelfill consists of tailings, different binders such as Portland cement, fly ash and blast furnace slag and an alkali activator such as sodium silicate. The CHF and Gelfill samples with various mixture designs were cast and cured for 28 days. The influence of sodium silicate concentration, pulp density and mixing time on the mechanical properties of samples were evaluated using the uniaxial strength test. Mercury intrusion porosimetery (MIP) was used to analyse the microstructure of CHF and Gelfill samples.This study concludes that: (i) The mechanical properties of CHF can be improved by the addition of appropriate amount of sodium silicate. (ii) The rate of strength acquisition in Gelfill samples is faster than CHF samples over 28 days of curing period. (iii) Mixing time strongly influences the mechanical properties of Gelfill samples but did not have any effect on CHF samples. (iv) The MIP analyses indicate that the pore size distribution and total porosity of Gelfill and CHF were different, and this did contribute to higher strength development of the Gelfill samples. INTRODUCTIONThe increased depths of mines in the Canadian Shield and the high stress associated with these depths favour a new method of mine backfill that can both meet strength requirements and help mine productivity. The mine backfill mainly consists of tailings, water and binder materials, the latter being most expensive. Gelfill is a new mine backfill material whose binder usually consists of alkali activators such as sodium silicate and other cementitious materials such as blast furnace slag and normal Portland cement. Although sodium silicate has been used in concrete manufacture, the use of this material in mine backfill is relatively new (Doucet, 2007, Razavi, 2007). Until very recently there have been only a few isolated publications, mostly out of McGill University, regarding mine Gelfill (Razavi, 2007 and Kermani et al., 2009 and 2010). These papers have investigated some of the basic mechanical properties and mechanical behaviour of Gelfill. However, the physical performance of Gelfill in various conditions has yet to be understood. Therefore, the main objective of this study was to investigate the influence of mixing time and sodium silicate concentration on the mechanical performance of Gelfill and CHF through a series of experiments. Moreover, the microstructure of the Gelfill and CHF samples was studied."

Jan 1, 2015

By W. Kempson

"Mining Companies have producing assets in increasingly diverse portions of the world. It is not uncommon that the owner, the design team, the mine contractors and the operators are all based in different countries. While these assets are always subject to the regulatory requirement of those countries there have not been international standards available to review and evaluate these assets. This becomes particularly important when considering safety critical items such as tailings dams, vertical shaft systems and autonomous vehicles to highlight a few. The work currently being completed in ISO ensures these standards will be available and will be generated by and subscribed to on an international basis, thus removing the potential for patriotic partisanship and ensuring safe and predictable systems are installed. This paper will discuss the benefits of the international standards, the structure of the teams and working groups who are generating these standards as well as the process by which the standards are generated. This will allow insight into the creation of the standard and will aim to demonstrate the “neutral” and technically strong manner in which the generation of these standards is achieved. In addition, the paper will discuss the standards which have been produced in the last five years as well as the current standards which are in place. The finale will discuss upcoming work and the timelines in which it is anticipated these will be completed. INTRODUCTION Mining Companies have producing assets in increasingly diverse portions of the world. While these assets are always subject to the regulatory requirement of those countries, there have not been international standards available to review and evaluate these assets. This becomes particularly important when considering safety critical areas such as vertical shaft systems, tailings dams and autonomous vehicles to highlight a couple. The work currently being completed in the International Organization for Standardization (ISO) ensure these standards will be available and will be generated by and subscribed to on an international basis, thus removing the potential for patriotic partisanship and ensuring safe and predictable systems are installed. The ISO/TC 82 – Mining was founded in 1955. This was an active committee until it was thought that the standards at the time were adequate and the Technical Committee was put on “Care and Maintenance”. In 2012 countries lobbied ISO to pull this committee from dormancy and restart it, this happened in in the same year."

Jan 1, 2019

"AbstractThe Sedimentary Basin area of Western Canada, which lies between the Precambrian Shield and the Cordilleran mountain area, covers approximately 800,000 square miles. Sediments ranging in age from Cambrian to Tertiary are present and, of these, horizons in the Upper and Lower Cretaceous, Jurassic, Mississippian, and Devonian have yielded commercial oil and gas flows. Producing horizons in the Cretaceous and Jurassic are sandstone, while all those of the Palaeozoic are carbonate rocks such as red limestone or dolomite (bioherms). Shows of oil and gas have been encountered also in the Cambrian and Triassic sediments.The broad structural features of this vast expanse of sedimentary rocks are the Moose Jaw syncline, the Sweet Grass-Battle River arch, the Alberta syncline, the Foothills belt, the Rocky and Mackenzie mountains, the Great Bear-Slave Lake basin, and the Mackenzie Delta Basin area.This contribution outlines the .stratigraphy and structure of the Basin area, and gives examples of present producing oilfield structures and stratigraphic traps.Part 1.-Regional StratigraphyIntroductionThe vast expanse of relatively undisturbed sedimentary rocks of western Canada has long been recognized as prospective territory to search for oil and/ or gas. This search in western Canada dates back before the turn of the century, but, considering the size of area to be explored and tested, the effort an<l money expended upon it, which, before the recent discovery of oil at Leduc, Alberta, appeared large and fruitless, now seems almost ridiculously small. A check-up of effort and money expended prior to and since the Leduc discovery would undoubtedly reveal that more wildcatting and development has taken place during the last two and a half years than during all previous years combined. The figures would astound not only the average citizen, but many within the industry itself."

Jan 1, 1950

By Sylvie Lévesque, Frederic Couët, Laura Pérez-Barnuevo, Cory Hennessey

Determining mineralogical characteristics of samples throughout the iron ore concentration process – from drill core samples up to the concentrate – is critical to process improvement and remediation. However, assessment of mineral proportions, liberation, and texture, although essential, can be time-consuming and costly. Thus, a mineralogical study is often not performed or only restricted to a limited number of samples. New iron ore deposits or new ore zones in active mines will bring new challenges as they are known to be problematic due to their lower grades, complex textures and presence of mineral impurities. In those cases, applied process mineralogy will be necessary to understand and to diagnose potential processing issues. To take full advantage of mineralogical information along the iron ore concentration process, new tools are being developed to provide mineralogical data based on texture, composition and liberation. In an early stage at the mine, the automated identification of drill core textures could provide essential information for the prediction of ore concentrability and grindability. In a later stage, the automated modal tool, combining the knowledge of the iron ore mineralogy of a specific deposit and the results of chemical analyses, can quantify the mineral proportions of the ore; results show good agreement between mineral estimation via chemical analysis and modal analysis using a Mineral Liberation Analyser. A bulk mineralogical analyser allowing semi-quantitative evaluation of the liberation of iron oxides is being validated. The results from the bulk mineralogical analyser will eventually be linked with the mineral proportions issued by the automated modal tool to provide complete mineralogical characteristics of iron ore samples. Ultimately, these mineralogical tools could provide valuable and timely insight for predicting concentrators’ performances or troubleshooting gravity separation processes.

Jan 1, 2016

By K. H. Poulsen, C. J. . Hodgson

Synvolcanic, layered gabbro-anorthosite sills at Rainy Lake, Northwestern Ontario, reflect a combination of igneous processes including fractional crystallization, wall rock assimilation and possibly liquid immiscibility. Chalcopyrite-pyrrhotite mineralization at the base of the Grassy Portage intrusion accumulated by crystallization of a sulphide liquid during cooling. Upward enrichment of Fe and Ti in this intrusion and also in the Bad Vermilion Lake anorthosite complex culminated with the crystallization of lenses of disseminated to massive magnetite+ apatite+ ilmenite+ rutile. Regional low to medium grade metamorphism and accompanying deformation resulted in recrystallization and local remobilization of ore minerals.

Jan 1, 1984